This invention relates to an ostomy coupling which may optionally be used with a gas vent and filtering means. It also relates to a filter cartridge.
The prior art is replete with suggestions intended to permit flatus gases to be vented from an ostomy bag. Many such arrangements included means for deodorizing these gases by the use of filters of various kinds. One successful ostomy bag and coupling arrangement is disclosed in British Pat. No. 1 571 657 of Kingsdown Medical Consultants Limited. As illustrated in FIG. 5 of that patent, a passageway radially through a coupling element allows escape of gas. In British Pat. No. 2 121 902, a bagside coupling element includes structure providing a recess which may house filter material. The bag wall is punctured to allow gas to escape from the bag into the recess, from which it escapes to atmosphere through a slit in the housing wall after having passed through a filter pad. An ostomy coupling element which is integral with a filter housing that can be closed by a snap-in cover is disclosed in British patent application Ser. No. 2 177 926A. A similar concept employing a separate filter housing is disclosed in U.K. patent application Ser. No. 2 202 147.
These and other attempts at achieving satisfactory deodorization of flatus gases have met certain needs but have increased the complexity of manufacture of ostomy bags, and the inventory which manufacturers need to carry, because of the need to manufacture two kinds of bag, namely those with filters and those without. Moreover, a patient having having purchased non-filter bags cannot change over to using a filter type without scrapping his stock of bags and purchasing new ones.
It would be desirable if there existed a bagside coupling for an ostomy bag which was satisfactory on a non-filter type bag but which could still be used, without modification, if the wearer wished to employe a filter.
It is an aim of the invention to meet this need.